Near the height of the war against the Islamic State group in Syria, a sudden riot of explosions rocked the country’s largest dam, a towering, 18-story structure on the Euphrates River that held back a 25-mile-long reservoir above a valley where hundreds of thousands of people lived.
The Tabqa Dam was a strategic linchpin controlled by the Islamic State group. The explosions March 26, 2017, knocked dam workers to the ground. A fire spread and crucial equipment failed. The flow of the Euphrates River suddenly had no way through, the reservoir began to rise and authorities used loudspeakers to warn people downstream to flee.
The Islamic State group, the Syrian government and Russia blamed the United States, but the dam was on the U.S. military’s “no-strike list” of protected civilian sites, and the commander of the U.S. offensive at the time, then-Lt. Gen. Stephen J. Townsend, said allegations of U.S. involvement were based on “crazy reporting.”
In fact, members of a top secret U.S. special operations unit called Task Force 9 had struck the dam using some of the largest conventional bombs in the U.S. arsenal, including at least one BLU-109 bunker-buster bomb, according to two former senior officials. And they had done it despite a military report warning not to bomb the dam, because the damage could cause a flood that might kill tens of thousands of civilians.
The decision to strike the dam would normally have been made high up the chain of command. But the former officials said the task force used a procedural shortcut reserved for emergencies, allowing it to launch the attack without clearance.
The two former officials, who spoke on the condition that they not be named because they were not authorized to discuss the strikes, said some officers overseeing the air war viewed the task force’s actions as reckless.
Even with careful planning, hitting a dam with such large bombs would likely have been seen by top leaders as unacceptably dangerous, said Scott F. Murray, a retired Air Force colonel.
“Using a 2,000-pound bomb against a restricted target like a dam is extremely difficult and should have never been done on the fly,” he said. “Worst case, those munitions could have absolutely caused the dam to fail.”
After the strikes, dam workers stumbled on an ominous piece of good fortune: Five floors deep in the dam’s control tower, a U.S. BLU-109 bunker buster lay on its side, scorched but intact — a dud. If it had exploded, experts say, the whole dam might have failed.
In response to questions from The New York Times, U.S. Central Command, which oversaw the air war in Syria, acknowledged dropping three 2,000-pound bombs but denied targeting the dam or sidestepping procedures. A spokesperson said that the bombs hit only the towers attached to the dam, not the dam itself, and while top leaders had not been notified beforehand, limited strikes on the towers had been preapproved by the command.
“Analysis had confirmed that strikes on the towers attached to the dam were not considered likely to cause structural damage to the Tabqa Dam itself,” said Capt. Bill Urban, the chief spokesperson for the command. Noting that the dam did not collapse, he added, “That analysis has proved accurate.”
But the two former officials, who were directly involved in the air war at the time, and Syrian witnesses interviewed by the Times, said the situation was far more dire than the U.S. military publicly said.
Critical equipment lay in ruins and the dam stopped functioning entirely. The reservoir quickly rose 50 feet and nearly spilled over the dam, which engineers said would have been catastrophic. The situation grew so desperate that enemies in the yearslong conflict — the Islamic State group, the Syrian government, Syrian defense forces and the United States — called an emergency cease-fire so civilian engineers could race to avert a disaster.
Engineers who worked at the dam, who did not want to be identified because they feared reprisal, said it was only through quick work that the dam and the people living downstream of it were saved.
“The destruction would have been unimaginable,” a former director at the dam said.
The United States went into the war against the Islamic State group in 2014 with targeting rules intended to protect civilians and spare critical infrastructure.
But the Islamic State group sought to exploit those rules, using civilian no-strike sites as weapons depots, command centers and fighting positions. That included the Tabqa Dam.
The task force’s solution to this problem too often was to set aside the rules intended to protect civilians, current and former military personnel said.
Soon, the task force was justifying the majority of its airstrikes using emergency self-defense procedures intended to save troops in life-threatening situations, even when no troops were in danger. That allowed it to quickly hit targets — including no-strike sites — that would have otherwise been off-limits.
Perhaps no single incident shows the brazen use of self-defense rules and the potentially devastating costs more than the strike on the Tabqa Dam.
It is unclear what spurred the task force attack March 26.
Dam workers said they saw no heavy fighting or casualties that day before the bombs hit.
What is clear is that Task Force 9 operators called in a self-defense strike, which meant they did not have to seek permission from the chain of command.
A military report obtained through a Freedom of Information Act lawsuit shows the operators contacted a B-52 bomber and requested an immediate airstrike on three targets. But the report makes no mention of enemy forces firing or heavy casualties. Instead, it says the operators requested the strikes for “terrain denial.”
A senior Defense Department official disputed that the task force overstepped its authority by striking without informing top leaders. The official said the strikes were conducted “within approved guidance” set by Townsend, the commander of the campaign against the Islamic State group.
First, the B-52 dropped bombs set to explode in the air above the targets to avoid damaging the structures, the senior military official said. But when those failed to dislodge the enemy fighters, the task force called for the bomber to drop three 2,000-pound bombs, including at least one bunker buster, this time set to explode when they hit the concrete.
Two workers were at the dam that day. One of them, an electrical engineer, recalled Islamic State fighters positioned in the northern tower as usual that day, but no fighting underway when they went into the dam to work on the cooling system.
Hours later, a series of booms knocked them to the floor. The room filled with smoke. The engineer found his way out through a normally locked door that had been blown open. He froze when he saw the wings of a U.S. B-52.
The dominoes of a potential disaster were now in motion. Damage to the control room caused water pumps to seize. Flooding then short-circuited electrical equipment. With no power to run crucial machinery, water couldn’t pass through the dam. There was a crane that could raise the emergency floodgate, but it, too, had been damaged by fighting.
The engineer hid inside until he saw the B-52 fly away and then found a motorcycle. He sped to the house where the dam manager lived and explained what had happened.
Engineers in Islamic State territory called their former colleagues in the Syrian government, who then contacted allies in the Russian military for help.
A few hours after the strike, a special desk phone reserved for directed communications between the United States and Russia started ringing in an operations center in Qatar. When a coalition officer picked up, a Russian officer warned that U.S. airstrikes had caused serious damage to the dam and there was no time to waste, according to a coalition official.
Less than 24 hours after the strikes, U.S.-backed forces, Russian and Syrian officials and the Islamic State group coordinated a pause in hostilities. A team of 16 workers — some from the Islamic State group, some from the Syrian government, some from U.S. allies — drove to the site, according to the engineer, who was with the group.
They succeeded in repairing the crane, which eventually allowed the floodgates to open, saving the dam.
The U.S.-backed Syrian Democratic Forces dismissed reports of serious damage as propaganda. A spokesperson said the coalition had struck the dam with only “light weapons, so as not to cause damage.”
A short time later, Townsend denied the dam was a target and said, “When strikes occur on military targets, at or near the dam, we use noncratering munitions to avoid unnecessary damage to the facility.”
No disciplinary action was taken against the task force, the senior officials said. The secret unit continued to strike targets using the same types of self-defense justifications it had used on the dam.